Nations Technologies Inc.
Tel
:
+86-755-86309900
:
Address: Nations Tower, #109 Baoshen Road, Hi-tech Park North.
Nanshan District, Shenzhen, 518057, P.R.China
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631
Figure 25-6 Loopback silent mode
CAN Debugging mode
CAN can continue to work normally or stop working according to the state of the following configuration bits:
DBG_CTRL.CAN_STOP bit of CAN in the debug support(DBG) module.See paragraph 27.3.2 Section:
Peripheral debugging support.
CAN_MCTRL.DBGF bit see paragraph 25.7.3.1 Section: CAN_MCTRL.
When the microcontroller is in debug mode, Cortex-M4F core is in a suspended state.
CAN function description
Send processing
The process of sending messages is as follows:
The application program selects an
empty
sending mailbox;
Writes the identifier, data length and data to be sent in the sending mailbox register;
Set the CAN_TMIx.TXRQ bit to request transmission(after CAN_TMIx.TXRQ is set the mailbox is no longer
an empty mailbox and the software has no permission to write to the mailbox register);
The mailbox enter the
pending
state and wait to be the highest priority, see 25.4.1.1 Send priority;
Changing to the
Ready
sending status once the mailbox becomes the highest priority mailbox;
The messages in the
Ready
state mailbox is sent as soon as the CAN bus enters the idle state, then enter the
CAN-CTRL
Tx
Rx
transceiver
1
CAN_Bus